Calculator.



W. E. 8: E. E. THOMPSON.

GALOULATOB.

APPLIOATIOK FILED DBO. 2, 1911.

' Patented May 7, 191 2.

3 SHEETS-SHEET 1.

E ma/Min (\i and EE Thom v.90 n,

W. B. 6: E. THOMPSON.

CALCULATOR, APPLIOATIOI FILED D120. 2, 1911' Patented May 7, 1912.

3 SHEETS-SHEET 2.

WE and Th0 m mron,

W. 5.. 6; E. B. THOMPSON. CALCULATOR.

APPLICATION FILED DEC. 2, 1911.

Patented May 7, 191 2.

3 SHEETS-SHEET 3.

UNITED STATES PATENT OFFICE.

WILLIAM E. THOMPSON AND EMMA E. THOMPSON, OF BANG-ER LAKE, NEW MEXICO.

CALCULATOR.

Specification of Letters Patent.

Patented May 7, 1912.

To all whom it may concern:

Be it known that we, WILLIAM E. THOMP- SON and EMMA E. THOMPSON, citizens of the United States, residing at Ranger Lake, in the county of Ghaves and State of New Mexico, have invented certain new and'useful Improvements in Calculators, of which the following is a specification.

This invention relates to machines for mechanically performing the mathematical operation of addition, and it has for its object to provide a machine of this kind which can be easily and rapidly operated, and which is devoid of complicated parts to get out of order.

The invention also has for its object to provide a novel and improved key-operated mechanism for actuating the registering devices, together with certain improved structural details to be-hereinafter described and claimed.

In order that the invention may be better understood, reference is had to the accompanying drawings forming a part of this specification, in which drawingsF1gure 1 is a front elevation of the machine. Fig. 2

is anend elevation of the registering mechanism, the casinginclosing the same being shown in section. Fig. 3 is a section on the line 33 of Fig. 2. Fig. 4 is a bottom plan view of the key-actuated arms to be hereinafter described. Fig. 5 is a plan view of the registering mechanism. Fig. 6 is a sectional detail of a portion of said mechanism. Fig. 7 is a perspective view of a modified structure.

Referring specifically to the drawings, 10 denotes a suitable casing which incloses the mechanism. In the front wall of the casing is a sight opening 11 through which the results are dis layed. The front of the casing also has a orward bottom extension 12 in the top of which are apertures through which the stems 13 of the several keys extend. It will be noted that two groups of keys are provided. The group to the right contains nine keys, these keys being the digit keys, and'being numbered from 1 to 9, re-

v spectively. The group to the left contains four keys. These keys represent units, tens, hundreds, and thousands, respectively. The number of keys in the last-mentioned group may be increased if the machine is designed for greater sums than thousands.

Suitably supported within the casing 10 is a stationary shaft 14.- on which are loosely mounted, for independent rotation thereon, four gear wheels, 15, 16, 17 and 18, respectively. These wheels, it will be noted, correspond in number to the group of keys at the left of the machine, and they may be termed units, tens, hundreds, and thousands wheels. To each wheel is rigidly connected, so as to turn therewith, a ratchet wheel 19, with spacing washers therebetween.

To the shaft 14 is pivoted a lever 20 and below said lever is a supporting frame 21 to which are pivoted arms 22 connected by rods 23 to the levers 24 of the respective digit keys, said levers being fulcrumed intermediate their ends on a rod 25. Thearms 22 are of difierent lengths, and their pivots 22 are in alinement. The lever of the digit key 1 is connected to the shortest arm, the lever of the digit key 2 to the next arm, and so on throughout the entire series, the lever of the digit key 9 being connected to the longest arm. The point of attachment of each rod 25 to the arms 22 coincides with the pivot of the next succeeding shorter arm. Thus, the rod which connects the lever of the digit key 9 to the longest arm is opposite the pivot of the arm to which the lever of the digit key 8 is connected.

It will be evident from the fore oing that the arms swing through arcs of magnitudes when the digit keys are operated, the arm to which the digit key 9 is connected making the greatest swing, and the arm to which the digit key 1 is connected making the smallest swing. The motion of the arms 22 is transmitted to-the lever 20 by a stem 26 pivotally connected at one of its ends to the free end of said lever and depending therefrom, and having its other endwidened'and formed with a knife ed e resting on the free-ends of the arms 22, said ends being in alinement and havingnotches,

different which latter are also in alinement to form a groove 27 in which the knife edge of the stem 26 seats. Inasmuch as the arms 22 have a variable swing, it will be evident that the lever 1s also given a variable swing when the digit keys are operated. Thus, a minimum swing is given the lever when the digit key 1 is operated, whereas a maximum swing is given the lever when the digit key 9 is operated. p

A mechanism to be presently described imparts motion to the wheels 15, 16, 17 and 18, and by the variable swing of the lever 20 Said wheels are moved the desired number of steps. When the digit key 1 is operated, the wheels move one step, when the digit key .2 is operated, the wheels are moved two seps, and so on, the number ofsteps progressing by one until the key 9 is reached which moves the wheels nine steps.

A spring 28 is connected to the lever 20 for the purpose of restoring the same to its normal position after been operated.

The following mechanism transmits the motion of the lever 20 to the wheels15, 16, 17 and 18: To the pivoted end of the lever 20 is rigidly connected a fork, the branches the digit keys have 29 of which are also pivotally connected to the shaft 14. The fork branches carry a housing 30 to. which is pivoted at one of its ends on a transverse rod 31 carried by the housing, an arm 32. 0n the rod 31 is pivotally mounted a spring-pressed pawl 33 having in its bottom edge a shoulder 33 engaged by a stud 33 carried by the arm 32. The pivoted end of the arm also has a stud 34 .over which fits one end' of a coiled spring 34, the other end of which abuts against the top of the housing 30. A. pawl and support therefor as herein described is provided for 'each ratchet wheel 19. The function of the spring 34 is to swing the arm 32 upwardly so that the pawls will be free of the respective ratchet wheels, this being their normal position. The supporting arm 32 of the pawl of the units ratchet wheel is connected to the units key, the supporting arm of the pawl of the tens ratchet wheel to the tens key, and so on in the same order throughout the series. The connections are such that when any one of the units, tens, etc., keys is depressed, the corresponding pawl is placed in operative position. Thus, when the tens key is' depressed, the pawl of the ratchet wheel of the tens wheel is placed inoperative position, and then upon depress- :ing, say, the digit key '3, the tens wheel is rotated three steps. The units, tens, etc., keys therefore select the wheels which are to be operated by the digit keys 1 to 9.

' The connection between the units, tens,

osses;

means of wires 35 connected at one of their ends to said keys, and at their other ends to loops36 connected to the free ends of the arms. The shaft 14 passes loosely through the loops, and the free ends of the arms have slots 37 through which loosely pass pins 38 connecting the loops to the arms. Upon depressing one of the units, tens, etc., keys, the arm 32 to which saidkey is connected swings down until it is stopped by the shaft 14, and the pawl carried by said arm then engages the corresponding ratchet wheel 19, whereupon the mechanism is ready for the operation of the lever 20. The slots 37 allow the connections 38 to move back and forth, and permit the motion produced by the lever 20.

It will be noted that all the wires 35 and loops 36 do not extend in a straight line to the keys, in view of which the loop will have a slight sidewise movement when it is swung downward, which, however, will not be great enough to interfere with or prevent the proper operation, but if more than four keys are employed, an auxiliary lever 39 is employed for each additional key. This lever has one of its ends connected by a link 39 to the key, and has connected adjacent to its other end the wire 35, the point of connection being located directly beneath the shaft 14, so that the wire runs in a straightline upward to the connection with the arm 32. .Fig. 7 of the drawing illustrates this mechanism.

In mesh with the respective gear wheels 15, 16, 17 and 18 are pinions 40, 41, 42 and 43. The pinion 40 is fast on an arbor 44 carrying a dial 45 provided with a numbered'face, the numbers running from zero to ,9 and being arranged in a circular series. This is the units dial. Tens, hundreds, and thousands dials 46, 47 and 48 are also provided, they being arranged concentrically and superposed on the dial 45, and each succeeding dial being smaller in diameter than the preceding one, so that the numbers of the several dials may be visible through the sight opening 11. The dial 46 is carried by the arbor 49 of the pinion 41, the dial 47 by the arbor 50 of the pinion 42, and the dial 48 by the arbor 51 of the pinion 43. The pinions are fast on the arbors, and the latter, with the exception of the arbor 51, are hollow and arranged one within the other, the arbor 51 being at the C911? ter. Each arbor turns, independently of the others, and each pinion has ten teeth.

The transfer mechanism for transmitting motion from the gear wheel 15 to the gear wheel 15 is a pinion 52 which is fast on a shaft 53 on which is also fast, a wheel 54 having one tooth. The pinion 52 has ten teeth. The toothed wheel 54 isso posit-lonecl that itcomes in mesh with the gear wheel 16 every time the pinion 52 makes one complete revolution. It will therefore be evident that for every ten steps of the gear wheel 15, the gear wheel 16 makes one step.

Asimilar mechanism'transmits the motion of-the 'gear'wheel 16 to the gear wheel 17, and the motion of the latter to the gear wheel 18. The shaft of the transfer mechanism betweenthe gear wheels 16 and 17 is indicatedat 55, and that of the transfer .mechanism between the gear wheels 17 and 18 is indicated at 56. Thus it will be seen that each dial when passing ten steps will. register its proper value/on the next higher dial. ""The shafts 53, 55 and 56 project through't-he front wallof the casing and on the projecting end of each shaft is fixed a small pointer-"or hand 57 by means of which the shafts'may be turned back, beginning with the shaft 53, 'to return the toothed wheels and at the same time the gear wheels to zero position.'. Index marks 58 on the casing indicatelhe position 'to which the pointers have to be turned to place the parts in zero position. The thousands gear wheel 18 isset back to zero by a pointer 59 on a-shaft 60 which carries a pinion 61 in "mesh with said gear wheel. Overthrow preventers are also provided, the same comprising spring-pressed pawls 62 engageable with the gear wheels 15, 16, 17 and 18.

Assuming it is desired to add 346,. 254,

and 520, the operation of the machine is as follows: Beginning at the first number, press 0346. "The next numbers are registered the units key and the digit key 6, whereu on the si ht opening 11 displays 0006. llien press it e-tens key and the digit key 4,

whereupon'the sight opening displays 004:6.

Thenpress the hundreds key and the digit key 3, Fwhereupoh the-sight opening dlsplalys y pressing the proper units and digit keys, the

- operatlon being continued until all the numbers have been registered, whereupon the sum of the several numbers, to wit, 1120, is displayed at the sight opening. The machine is then set back to zero and is ready 'fifir the next operation.

The sum can also found by adding all the units figures, then the tens, etc.

It will be understood, of course, that when I any one of the gear wheels 15, 16, 17 and 18 has taken-'tensteps, the result will be transferred to the next higher one n the series.

1 60 Thus, when t is added to 346, the units gear wheel 15 will have taken ten steps, the pinion 52 has been given one revolution, and

pawls, pivoted arms arranged to swing through. arcs of different magnitudes. a conoperatively connected to the arms, and keyoperated meansfor placing the pawls in operative position with respect to a selected register wheel. ap 2; In a calculator, a plurality of register Wheels ofdifferent-orders, a transfer mechanism for said wheels, a ky-actuatedpawland-ratchet mechanism for operating the register wheels, and key-operated means for placing the pawls in operative position with respect to a selected register wheel.

3. In a calculator, a plurality of register wheels of different orders, a transfer mech= anism for said wheels, a key-actuated pawland-ratchet mechanism for operating the register wheels, .means for normally holding the pawls in inoperative position, and keyoperated means for placing the pawls in operative position'with respect to a selected register wheel. l

4:. In a calculator, a plurality of register wheels of different orders, a transfer mechanism for said wheels, means for operating nection between the armsandthe lever, keys the register Wheels, said means including a lever, i'voted arms swinging through arcs of di erent magnitudes, and keys operatively connected tothe arms, and key-oper ated means for placing the operating means of the register wheels in operative position with respect to a selected register wheel.

5. In a calculator, a plurality of register wheels of different orders, a transfer mechanism for said wheels, a key-operated lever having a variableswing, pawls carried .by the lever for actuating the register wheels,

arms carried by the lever, means on the arms for lifting the pawls into inoperative position, and keys operatively connected to the arms for actuating the same to place the pawls in operative position.

6. In a calculator, a plurality of register wheels of different orders, a-transfer mechanism for said wheels, a key-operated lever having a variable swing, pawls carried by the lever for actuating the register wheels, arms carried by the lever, studs on the arms engugeable with the pawls, springs engageable with the arms for swinging the latter into position to place the pawlsin inoperative position, and keys operatively connected to the arms for swinging the same to place the pawls in operative position.

7. In a'calculator, a register Wheel, and means for operatin said wheel, said means including a lever, 21 series of pivoted arms of different lengths, a connection between the lever and the arms, and keys operatively connected to the arms, the point of attachment of said connection'to each arm coinciding with the pivot of the next shorter arm in the series.

In testimony whereof We afiiX our signatures in presence of two witnesses.

W ILLIAM E. THOMPSON. EMMA E. THOMPSON. Witnesses:

BUD B. WISE, J 1M TURNER. 

